This invention relates to a device for carrying a supply of material from which small portions may, from time to time, be separated from the supply for use as desired. The invention is particularly adaptable to what may be termed as a fountain brush. This type of mechanism allows for dispensing of a plastic or liquid type material, such as toothpaste or a cleansing material to the bristles of a brush (or something similar such as a sponge or felt pad).
Typical of the prior art are U.S. Pat. No. 1,538,225 to Stockseth and U.S. Pat. No. 1,325,268 to Sosdian. The Stockseth patent shows a device whereby a screw-fed piston forces fluid from a reservoir to the brush. The Sosdian patent discloses a reservoir having a spring-biased piston therein where fluid is allowed to flow from the reservoir to the brush upon the opening of a manually-controlled normally closed valve. Unfortunately these type of devices have proved unsatisfactory for various reasons. For example, the Stockseth device provides for annoyingly slow screw feed of the fluid to the bristles with limited control over stopping the flow once it starts, i.e., additional rotation of the shaft is required to either close the outlet or reverse the movement of the piston. With the Sosdian invention, control is also difficult because it varies greatly with the amount of material in the reservoir. Thus, the pressure exerted by spring 15 is greatest when the reservoir is fullest, but this decreases markedly as the reservoir empties. Thus, the user never knows how much fluid will be dispensed for a given amount of time that the valve is left open.
Some other prior art that is of interest are U.S. Pat. No. 3,284,838 to Bieganowski and U.S. Pat. No. 2,948,007 to Tanguay. The Bieganowski patent discloses a reservoir which is separate from the brush, i.e., a fluid line running through the brush connects the reservoir, a pressure pump, to the brush bristles. No chamber or piston-like device is provided within the brush. The Tanguay patent discloses a device having a piston made up of two telescopic parts. However, this device also suffers from the same problem of the prior art such as with the Stockseth patent in that each of the telescopic parts are threaded and the inside of the housing is threaded to allow for movement of the piston to compress the fluid. This then only allows for slow and inaccurate control of the fluid flow from the chamber.